MDEK1001 - Can't connect via BLE on Win10

I’m trying to setup a 1 Anchor + 1 Tag configuration. I’m planning to communicate with the tag by custom Qt desktop Win 10 app and its Bluetooth Low Energy api. As for now I have a problem even to connect with the MDEK1001. In the Qt app I can successfully connect with the tag, create the Node Characteristic Service (680c21d9-c946-4c1f-9c11-baa1c21329e7), but I am unable to read any characteristic in it. Even the example lowenergyscanner Qt app can’t read any of the characteristics. I tried to pair it first using Win 10 system bluetooth tool. It finds the device when scanning but when I click it to pair, after a while I just get “Try connecting your device again” message. I tried also with the Bluetooth LE Explorer app from Microsoft Store, but have the same problem: can’t pair with the device at all.

Do I need to configure something first via UART in the module to successfully connect to it with bluetooth? Anyone managed to connect the module to the Win 10 pc? Can’t figure out what I do wrong.

Thanks in advance.